Granulators are part of a class of machines used to reduce scrap to chips or small pieces. These machines are used to regrind plastic parts for remelting and forming into new parts. Similar machines are used to grind trees and wood cuttings into mulch, grind automotive tires for recycling and chop electronic parts for separation of materials and precious metals. Screens are used in the cutting chambers to sort out pieces that are of a desired size. The pieces are cut or chopped until they are of a size to escape the cutting chamber and fall into the output bin or discharge.
The machines are configured to grind or chop a particular material with the blades selected to perform the necessary cutting action. The blades are formed from hardened steel or alloy and the cutting edge ground depending on the material to be processed. Continuous hard use and shocks to the blade may damage them requiring the place to be removed and be sharpened. The shock absorbed by the blade may be caused by foreign objects dropped into the hopper. Foreign objects such as nuts or bolts, personal jewelry, etc., may fall into the granulator from time to time and cause damage to the blades. The blades may also need to be resharpened after use.
Typically the blades on the rotary cutter are kept together in a set. The blades are ground to a preselected dimension. Likewise the bed blades are treated as a set and similarly ground together to a preselected dimension. The blades when assembled on the machine require a calibration of the rotary cutter and the bed blades to adapt the positioning for cutting in a desired dimension. Replacing the blades and adjusting the machine requires downtime of the machine. Further, the blades are expensive due to the high quality material used.
Multipart blades have been designed to use a hardened steel cutter blade attached to a soft steel carrier. These blades require a large carrier and fasteners are to absorb the shock of the cutting action. The weight of these blades make shipping the blade for resharpening expensive. In addition, the construction of these blades demands the blades be expensive. Accordingly, it is desirable to have a cutting blade that may be retrofitted on a standard rotor having an inexpensive, blade holder formed of plastic, composite or inexpensive metal and a cutter blade of tool steel removably Attached thereon. The cutter blade securely fastened to the blade holder and adapted to directly transferred the shock of the cutting action to the late holder. The cutter blade being removable from the blade holder to allow shipping only the cutter blade for resharpening.